The present invention relates to a compound, 3-phenyl-7-[4-(tetrahydrofurfuryloxy)-phenyl]-1,5-dioxa-s-indacene-2,6-dio ne, having a specific structure of crystals. More particularly, it relates to 3-phenyl-7-[4-(tetrahydrofurfuryloxy)phenyl]-1,5-dioxa-s-indacene-2,6-dion e which has a structure of crystals useful for dyeing or printing hydrophobic fiber materials particularly in a deep tint of colors.